The present invention relates to an improvement in the method employed to apply agricultural chemicals, such as herbicides, pesticides and fertilizers and more specifically, to an articulating sprayer boom hinge assembly for sprayers.
Liquid chemicals such as, herbicides and pesticides are commonly applied by use of a sprayer having long booms. This sprayer may be attached to a tractor, placed in the rear of a pickup, or be of a self-propelled nature. Typically, these sprayers will have long booms reaching out on either side to increase the area sprayed with each pass of the vehicle. As the boom length increases, so does the difficulty in moving the sprayer from one location to another as these booms must be placed in a transport or folded position. The folding of these booms is often accomplished manually by the driver of the rig. A second problem associated with boom length is the stability of the outer ends of the booms. As the boom length extends out from the vehicle pulling the sprayer, the ends of the booms are subject to more up and down movement as the vehicle travels over small bumps and ruts and thus, moves from side to side. A third problem with lengthening the booms is the tendency for the driver to misjudge distances from obstacles such as power poles, trees and fences, thus, running the end of the boom into the obstacles, possibly damaging the boom and the obstacle, and causing costly down time.
The aforementioned problems have been addressed separately by other patents. For example, U.S. Pat. No. 4,372,492 issued to Blumenshine in 1983 discloses a sprayer boom assembly having outer and inner wing sections of which the outer wing is automatically foldable against the inner wing through a translational to rotational movement arrangement. This sprayer is also configured with a breakaway outer spray boom. However, this patent does not allow the outer boom knuckle or flex in a vertical plane at the connection point between the outer and inner booms. This may cause severe vertical end movement of the outer boom as the center of the rig encounters small ruts or bumps. Another patent, U.S. Pat. No. 4,427,154 issued to Mercil, the inventor of present subject, also discloses a sprayer boom assembly. Again, on this boom assembly, the outer and inner boom connection point is solid, thus, not allowing the outer and inner boom to move in the vertical plane relative to each other. A still further invention, is U.S. Pat. No. 3,580,505 issued to Herbert V. Loeffler. This patent discloses a sprayer boom assembly which floats side to side in order to compensate as a vehicle moves over rough terrain, through ruts, or is tilted side to side.
As can be seen, none of the aforementioned patents have been able to disclose a boom assembly which may be folded horizontally by a powered means into a transport position or back into an in-use position, while also supplying a brake away mechanism which automatically resets, and the ability to allow the booms to float over rough terrain or ruts. From this discussion it can be seen that it would be desirable to produce a boom with these features.